WP 10 leader: James Orr (James.Orr (at) lsce.ipsl.fr) CEA

Objectives:

• Determine future changes in carbonate chemistry (pH, CaCO₃ saturation states, etc.) and associated uncertainties using a range of coastal-, basin-, and global-scale models.
• Identify critical regions (hot spots) where changes and variability in carbonate chemistry are largest.
• Assess commitment of past and future carbon emissions (i.e., the anthropogenic perturbation’s inertia after emissions are halted) in terms of future changes of carbonate chemistry.

Description of work and role of participants:

T10.1: Simulations - Use a hierarchy of models (high-resolution regional to global models) to simulate future carbonate chemistry over the 21st century and beyond focusing on changes in the North Atlantic, Arctic, European shelf seas, and upwelling systems (All partners: UiB, AWI, CEA, PML, MPG, UBern, ETH ZURICH)

T10.2: Model-data comparison - Rigorously evaluate models against existing data over the industrial period (link with WP2 and WP3) (All partners)

T10.3: Model-model comparison - Provide uncertainties by comparing models results to one another in critical regions (see above) where model domains overlap (All partners)

T10.4: Sensitivity studies - Perform sensitivity studies to determine how predicted ocean acidification changes (1) under a range of physical forcing and greenhouse gas scenarios in different models (All partners) and (2) with improved model resolution, i.e., a systematic comparison of coarse, eddy permitting, and eddy resolving versions of global and European shelf sea models (CEA, ETH ZURICH, PML)